Gender differences in mate selection criteria: Sociobiological or socioeconomic explanation?

Past research has demonstrated clear gender differences in reported mate selection criteria. Compared to women, men place more importance on physical attractiveness and women place more importance than men do on the earning capacity of a potential mate. These gender differences have been explained using both sociobiological propositions and differences in the relative economic power of men and women. The present study tested the structural powerlessness hypothesis as an explanation for women's greater emphasis on the earning capacity of a potential spouse. Samples of college students (N = 997) and community members (N = 282) were asked to report expected personal income and to rate the importance of listed characteristics in a potential mate. Consistent with past research, men placed more emphasis on the item Good Looks, whereas women placed more importance on the item Good Financial Prospect. Contrary to the structural powerless model, women's expected income was positively related to ratings of the importance of a potential mate's earning capacity in the college sample and was unrelated to women's ratings of the item Good Financial Prospect in the community sample. Findings are discussed in terms of both evolutionary psychology and gender differences in access to financial resources.     

Preferences for symmetry in human faces in two cultures: data from the UK and the Hadza, an isolated group of hunter-gatherers

Many studies show agreement within and between cultures for general judgements of facial attractiveness. Few studies, however, have examined the attractiveness of specific traits and few have examined preferences in hunter-gatherers. The current study examined preferences for symmetry in both the UK and the Hadza, a hunter-gatherer society of Tanzania. We found that symmetry was more attractive than asymmetry across both the cultures and was more strongly preferred by the Hadza than in the UK. The different ecological conditions may play a role in generating this difference. Such variation in preference may be adaptive if it reflects adaptation to local conditions. Symmetry is thought to indicate genetic quality, which may be more important among the Hadza with much higher mortality rates from birth onwards. Hadza men who were more often named as good hunters placed a greater value on symmetry in female faces. These results suggest that high quality Hadza men are more discriminating in their choice of faces. Hadza women had increased preferences for symmetry in men's faces when they were pregnant or nursing, perhaps due to their increased discrimination and sensitivity to foods and disease harmful to a foetus or nursing infant. These results imply that symmetry is an evolutionarily relevant trait and that variation in symmetry preference appears strategic both between cultures and within individuals of a single culture.     

How Universal Are Preferences for Female Waist-to-Hip Ratios? Evidence from the Hadza of Tanzania

Female waist-to-hip ratio (WHR) has been proposed by evolutionary psychologists to be an important component of human male mate choice, because this trait is thought to provide a reliable cue to a woman's reproductive value. Based largely on work conducted in industrialized societies, the claim has been made that preferences for low WHR are culturally invariant. Presumably, the preferences evolved before the advent of agriculture, making foraging populations the best place to test the hypothesis. This was done with the Hadza of Tanzania, who were shown figures of females that varied by weight and waist-to-hip ratio. Low WHR was not preferred. Hadza men did not consider waist-to-hip ratio when expressing preferences for mates. Instead, they were most interested in the weight of potential partners. Research by others with subjects who practice swidden agriculture also revealed that low WHR was not preferred. The data from the Hadza coupled with the information derived from this horticultural group bring into question whether preferences for low WHR are culturally invariant.     

Partner choice in human evolution: The role of cooperation,foraging ability,and culture in Hadza campmate preferences

The ability to choose the partners we interact with is thought to have been an important driver in the evolution of human social behavior, and in particular, our propensity to cooperate. Studies showing that humans prefer to interact with cooperative others is often cited as support for partner choice driving the evolution of cooperation. However, these studies are largely drawn from Western samples, where conditions for partner choice to operate may be especially favorable. Here, we investigate qualities associated with being a preferred partner (i.e., campmate) in Hadza hunter-gatherers of Tanzania in 2016 and 2019. A total of 156 Hadza participants from 17 camps ranked their campmates on generosity, foraging ability, and their preference for them as future campmates. In 2016, Hadza preferred more generous people and better hunters as campmates, with evidence suggesting a stronger preference for better hunters; however, the relationship between generosity and being a preferred campmate was greater in 2019 than in 2016, such that the preference for generous people was stronger than the preference for better foragers, suggesting that campmate preferences are changing. These new findings contrast with reports on data from nearly a decade ago, suggesting that the Hadza do not prefer more cooperative campmates. Further, in 2019, there was anecdotal evidence that Hadza with greater exposure to outside cultural institutions (e.g., schooling, having a job, or living in a village) had a stronger preference for generous campmates than those with less exposure. Taken together, the results suggest that preferences for social partners may, in part, be culturally shaped.     

Sex and Age Differences in Mate-Selection Preferences

For nearly 70?years, studies have shown large sex differences in human mate selection preferences. However, most of the studies were restricted to a limited set of mate selection criteria and to college students, and neglecting relationship status. In this study, 21,245 heterosexual participants between 18 and 65?years of age (mean age 41) who at the time were not involved in a close relationship rated the importance of 82 mate selection criteria adapted from previous studies, reported age ranges for the oldest and youngest partner that they would find acceptable, and responded to 10 yes/no questions about a potential marriage partner. For nearly all mate selection criteria, women were found to be the more demanding sex, although men placed consistently more value on the physical attractiveness of a potential partner than women. Also, the effects of the participants?? age and level of education were nearly negligible. These results demonstrate the robustness of sex differences in mate selection criteria across a substantial age range.     

Men''s preferences for women''s profile waist-to-hip ratio in two societies

Women's waist-to-hip ratio (WHR) varies with age, and a lower WHR is associated with a higher estrogen-to-androgen ratio and possibly higher fecundity, at least in some populations. Consequently, it has been argued that selection has favored a universal male preference for a low female WHR. In previous studies using frontal pictures, men in the United States preferred a low WHR of 0.7, but men among Hadza hunter–gatherers and a few other small-scale societies preferred higher ratios. Unlike the actual WHR of women, measured with a tape around the waist and the hips and buttocks, the WHR in frontal pictures excludes the buttocks. Because frontal WHR gives only a partial picture, we used profile views of women to measure men's preferences for the profile WHR. Hadza men preferred a lower profile WHR (more protruding buttocks) than American men. Since Hadza men preferred higher frontal WHR but lower profile WHR, and since both contribute to the actual WHR, these results imply there is less disparity between American and Hadza preferences for the actual WHR of real women. We suggest men's preferences vary with the geographic variation in the shape of women who have wider hips in some populations and more protruding buttocks in others.     

Demography of the Hadza, an increasing and high density population of Savanna foragers.

This is a report on the demography of the Hadza, a population of East African hunter-gatherers. In it, we describe the results of a census, and our estimation of age structure, survivorship, mean age of women at childbearing, number of live children, total population size and density, and rate of change since 1967. We show that relevant measures fit closely the stable population model North 6 chosen by Dyson to represent Hadza demography in the 1960s. We compare aspects of Hadza demography with surrounding non-Hadza and with the !Kung. Among other things, we find that the Hadza have a higher population density, higher fertility, and a faster population growth rate than do the !Kung. These demographic differences are consistent with our expectations, which were based on differences in the costs and benefits of foraging in the two regions. We also show that Hadza demographic parameters display remarkable consistency over the past 20 years. Since neighboring populations have been encroaching on the area used by the Hadza, and Hadza foragers have been subject to interludes of externally imposed settlement, this consistency is surprising. We discuss some of the implications.     

Mutualism and manipulation in Hadza–honeyguide interactions

We investigated the ecology and evolution of interspecific cooperation between the Greater Honeyguide bird, Indicator indicator, and human hunter-gatherers, the Hadza of northern Tanzania. We found that honeyguides increased the Hadza's rate of finding bee nests by 560%, and that the birds led men to significantly higher yielding nests than those found without honeyguides. We estimate that 8–10% of the Hadza's total diet was acquired with the help of honeyguides. Contrary to most depictions of the human-honeyguide relationship, the Hadza did not actively repay honeyguides, but instead, hid, buried, and burned honeycomb, with the intent of keeping the bird hungry and thus more likely to guide again. Such manipulative behavior attests to the importance of social intelligence in hunter-gatherer foraging strategies. We present an evolutionary model for human-honeyguide interactions guided by the behavioral ecology of bees, non-human primates, and hunter-gatherers.     

I Want What She’s Having

A variety of non-human females do not select male partners independently. Instead they favor males having previous associations with other females, a phenomenon known as mate copying. This paper investigates whether humans also exhibit mate copying and whether consistent positive information about a man’s mate value, and a woman’s age and self-perceived mate value (SPMV), influence her tendency to copy the mate choices of others. Female university students (N?=?123) rated the desirability of photographed men pictured alone or with one, two, or five women represented by silhouettes. In accordance with the visual arrays, men were described as currently in a romantic relationship; having previously been in one, two, or five relationships; or not having had a romantic relationship in the past 4 years. Women generally rated men pictured with one or two previous partners as more desirable than those with none. Men depicted with five previous partners, however, were found to be less desirable. Younger, presumably less experienced women had a greater tendency to mate copy compared with older women, but high SPMV did not predict greater levels of mate copying. The findings reaffirmed and expanded those suggesting that women do not make mate choices independently.     

Hunter-gatherer males are more risk-seeking than females,even in late childhood

Observed economic and labor disparities between the sexes may, in part, result from evolved sex differences in risk preferences. Using incentivized economic games, we report on sex differences in risk preferences in the Hadza, a population of hunter-gatherers. One game played in 2010 (n = 233) found that more Hadza males than females prefer to gamble for a chance to earn more maize rather than settle for a sure, but smaller, amount. Similarly, a second game played in 2013 (n = 102) found that male Hadza gamble a greater proportion of honey for a chance to earn more compared to female Hadza. Effect sizes are small to medium. We find weak evidence that risk-taking increases in men as their mating opportunities increase. In both games, the sex difference widens throughout childhood and is greatest among adolescents; though note that child samples are small. We explore developmental trends further using observational data on food returns in children (n = 357). Our data suggest that while the mean number of calories boys bring to camp remains stable with age, the variance in their caloric returns increases. Among girls, the variance remains stable with increased age. Both the economic games and food return data are consistent with the sexual division of labor wherein boys, beginning in late childhood, begin to target riskier foods. To the extent that the Hadza allow us to make inferences about long-standing patterns of human behavior, we suggest that sex differences in risk preferences may have been present long before agriculture and the modern work environment.     

Does Early Psychosocial Stress Affect Mate Choice?

Early psychosocial stress (e.g., parental divorce, abuse) is conjectured to place individuals on a developmental trajectory leading to earlier initiation of sexual activity, earlier reproduction, and having more sex partners than those with less early psychosocial stress. But does it also affect an individual’s mate choice? The present study examined whether early psychosocial stress affects preferences and dislikes for opposite-sex faces varying in masculinity/femininity, a putative indicator of mate quality, in premenopausal women (58 with a natural cycle, 53 pill-users) and 196 men. No significant three-way interactions were found when women selected the most or least preferred face with participant group (natural cycle, pill), conception risk (low, high), and early psychosocial stress (low, high) as between-subjects factors. Early psychosocial stress did not affect men’s face preferences when selecting the most preferred face. However, men with high early psychosocial stress disliked masculine faces significantly more so than men with low early psychosocial stress. Overall it was concluded that early psychosocial stress does not affect mate choice with the exception that men with high early psychosocial stress were more likely to dislike masculine female faces. It was suggested that men with high early psychosocial stress may dislike masculine female faces because they have nothing to gain from associating with women with such faces.     

Mate choice trade-offs and women’s preference for physically attractive men

Researchers studying human sexuality have repeatedly concluded that men place more emphasis on the physical attractiveness of potential mates than women do, particularly in long-term sexual relationships. Evolutionary theorists have suggested that this is the case because male mate value (the total value of the characteristics that an individual possesses in terms of the potential contribution to his or her mate’s reproductive success) is better predicted by social status and economic resources, whereas women’s mate value hinges on signals conveyed by their physical appearance. This pattern may imply that women trade off attractiveness for resources in mate choice. Here I test whether a trade-off between resources and attractiveness seems to be occurring in the mate choice decisions of women in the United States. In addition, the possibility that the risk of mate desertion drives women to choose less attractive men as long-term mates is tested. The results were that women rated physically attractive men as more likely to cheat or desert a long-term relationship, whereas men did not consider attractive women to be more likely to cheat. However, women showed no aversion to the idea of forming long-term relationships with attractive men. Evidence for a trade-off between resources and attractiveness was found for women, who traded off attractiveness, but not other traits, for resources. The potential meaning of these findings, as well as how they relate to broader issues in the study of sex differences in the evolution of human mate choice for physical traits, is discussed.     

Household and Kin Provisioning by Hadza Men

We use data collected among Hadza hunter-gatherers between 2005 and 2009 to examine hypotheses about the causes and consequences of men’s foraging and food sharing. We find that Hadza men foraged for a range of food types, including fruit, honey, small animals, and large game. Large game were shared not like common goods, but in ways that significantly advantaged producers’ households. Food sharing and consumption data show that men channeled the foods they produced to their wives, children, and their consanguineal and affinal kin living in other households. On average, single men brought food to camp on 28% of days, married men without children at home on 31% of days, and married men with children at home on 42% of days. Married men brought fruit, the least widely shared resource, to camp significantly more often than single men. A model of the relationship between hunting success and household food consumption indicates that the best hunters provided 3–4 times the amount of food to their families than median or poor hunters. These new data fill important gaps in our knowledge of the subsistence economy of the Hadza and uphold predictions derived from the household and kin provisioning hypotheses. Key evidence and assumptions backing prior claims that Hadza hunting is largely a form of status competition were not replicated in our study. In light of this, family provisioning is a more viable explanation for why good hunters are preferred as husbands and have higher fertility than others.     

Sex and age differences in preferences and tactics of mate attraction: Analysis of published advertisements

Using the theoretical perspective of evolutionary biology, 13 hypotheses were generated concerning sex and age differences in human mate preferences and tactics of mate attraction. Classified “lonely hearts” advertisements (N = 1,000) from a nationally circulated, fortnightly magazine were content-analyzed. Men, more than women, sought cues to reproductive value (i.e., physical appearance and youth), whereas women, more than men, sought cues revealing an ability to acquire resources (i.e., actual and potential financial security and older men). Women also sought to ascertain a man's willingness to provide resources (in the form of time, emotions, money, and status) in a relationship. Both sexes offered those traits sought by the opposite sex. Men were more promiscuously inclined than women, favoring casual relationships and being more likely to be married, whereas women sought long-term monogamous relationships. These differences support evolutionary predictions based on concepts of sexual selection, parental investment, and reproductive capacities and confirm the use of personal advertisements as a valuable method of research.     

Sex Differences in Hadza Dental Wear Patterns

Among hunter-gatherers, the sharing of male and female foods is often assumed to result in virtually the same diet for males and females. Although food sharing is widespread among the hunting and gathering Hadza of Tanzania, women were observed eating significantly more tubers than men. This study investigates the relationship between patterns of dental wear, diet, and extramasticatory use of teeth among the Hadza. Casts of the upper dentitions were made from molds taken from 126 adults and scored according to the Murphy dental attrition scoring system. Females had significantly greater anterior occlusal wear than males when we controlled for age. Males exhibited greater asymmetry in wear, with greater wear on the left side in canines, first premolars, and first molars. We suggest that these sex differences in wear patterns reflect the differences seen in the diet, as well as in the use of teeth as tools.     

Spousal age-gaps,partner preferences,and consequences for well-being in four Colombian communities

Across cultures, women tend to marry older men. This phenomenon is commonly described as the result of evolved mate choice preferences, which cause men to base reproductive decisions on cues of youth and fertility in women, and women to base such decisions on cues of wealth and status in men. Other researchers have challenged this idea, arguing that husband-older spousal age-gaps might not be consistent with the joint preferences of men and women; age-gaps might instead arise as the result of sexual conflict. In such cases, the realized age-gap could benefit one party at a cost to the other. In practice, large age-gaps may result in negative outcomes for younger women married to older men—e.g., because of power differences in these relationships. Testing for the existence of sexual conflict over the size of the spousal age-gap in Tanzania, researchers found no evidence that large age-gaps are harmful to women. Here, we conceptually replicate this previous work, and assess the relationship between spousal age-gaps, partner preferences, and individual well-being in four communities in Colombia. We extend prior methods by inferring the size of idealized age-gaps using network structured mate-choice games, and measuring the realized age-gap directly among ever-married partners. Our analyses suggest that there is limited evidence of sexual conflict over the size of the spousal age-gap in these communities. First, realized age-gaps are not large on average—around 1–7 years across communities. Second, the age-gaps that do exist are consistent with the preferences of both men and women—at least during their early to middle reproductive periods. And, lastly, large age-gaps are not negatively associated with measures of fertility or well-being for either sex. Our results underscore the importance of appreciating the cultural context within which behavioral practices with potentially negative consequences are situated.     

Variation in Male Reproductive Longevity across Traditional Societies

Most accounts of human life history propose that women have short reproductive spans relative to their adult lifespans, while men not only remain fertile but carry on reproducing until late life. Here we argue that studies have overlooked evidence for variation in male reproductive ageing across human populations. We apply a Bayesian approach to census data from Agta hunter-gatherers and Gambian farmers to show that long post-reproductive lifespans characterise not only women but also males in some traditional human populations. We calculate three indices of reproductive ageing in men (oldest age at reproduction, male late-life reproduction, and post-reproductive representation) and identify a continuum of male reproductive longevity across eight traditional societies ranging from !Kung, Hadza and Agta hunter-gatherers exhibiting low levels of polygyny, early age at last reproduction and long post-reproductive lifespans, to male Gambian agriculturalists and Turkana pastoralists showing higher levels of polygyny, late-life reproduction and shorter post-reproductive lifespans. We conclude that the uniquely human detachment between rates of somatic senescence and reproductive decline, and the existence of post-reproductive lifespans, are features of both male and female life histories, and therefore not exclusive consequences of menopause.     

Father's physique influences mate preferences but not the actual choice of male somatotype in heterosexual women and homosexual men

Body constitution plays an important role in human mate choice. Cross-cultural research reports that women on average prefer men with muscular physique. It is still unclear, however, what mechanisms influence the inter-individual variation in mate preferences and choices of partner's physique. In this study, we tested the mechanisms of an imprinting-like effect (similarity between father and an ideal and actual partner) and of homogamy (similarity between self and an ideal and actual partner) for male physique in heterosexual women and homosexual men. To assess the variation in male physique, we employed somatotype paradigm which characterizes body constitution using three components: endomorphic (heavy-set), mesomorphic (muscular), and ectomorphic (lean). In total, 149 homosexual men and 769 heterosexual women from the Czech Republic indicated the somatotype of their father, ideal and actual partner, and in homosexual men also their own somatotype. In line with previous research, the somatotype most preferred by both men and women was the mesomorphic, followed by the ectomorphic and the endomorphic one. Women's preferences for an ideal partner somatotype weakly correlated with their fathers' somatotype, especially in women who reported a positive relationship with their fathers during childhood. Among homosexual men, we found imprinting-like preferences only for the ectomorphic somatotype component and no significant association with the quality of their relationships with their fathers. We also found no significant relationship between the fathers' and actual partners' somatotype in either heterosexual women or homosexual men. Our research indicates that fathers have a rather weak influence on mate preference for somatotypes and no influence on actual mate choice.     

How the Harsh Environment of an Army Training Camp Changes Human (Homo sapiens) Facial Preferences

Previous studies suggest that facial preferences may be contingent on an individual's environment, yet no study has traced how the preferences of the same individuals change as their environment changes. We therefore sought to determine if, and to what extent, adiposity and masculinity preferences are malleable by repeatedly testing students whose environment was not changing as well as students undergoing intensive training at an army camp. Our results showed that at baseline, the students at the training camp preferred more feminine male faces. This suggests that even before the training commenced, participants in the training camp may have been in a psychological state that predisposed them to prefer more trustworthy (i.e., more feminine) men. Additionally, we found that the students at the training camp reported increases in multiple stressors as well as showed changes in adiposity preferences. More specifically, we found that increases in the harshness of the environment led to an increased male attraction to cues of higher weight in female faces. Such changes in preferences may be adaptive because they allow men more opportunities to mate with women who are better equipped to survive and reproduce. These findings thus provide new evidence for the malleability of preferences depending on the environment.     

Tubers as fallback foods and their impact on Hadza hunter-gatherers

The Hadza are hunter-gatherers in Tanzania. Their diet can be conveniently categorized into five main categories: tubers, berries, meat, baobab, and honey. We showed the Hadza photos of these foods and asked them to rank them in order of preference. Honey was ranked the highest. Tubers, as expected from their low caloric value, were ranked lowest. Given that tubers are least preferred, we used kilograms of tubers arriving in camp across the year as a minimum estimate of their availability. Tubers fit the definition of fallback foods because they are the most continuously available but least preferred foods. Tubers are more often taken when berries are least available. We examined the impact of all foods by assessing variation in adult body mass index (BMI) and percent body fat (%BF) in relation to amount of foods arriving in camp. We found, controlling for region and season, women of reproductive age had a higher %BF in camps where more meat was acquired and a lower %BF where more tubers were taken. We discuss the implications of these results for the Hadza. We also discuss the importance of tubers in human evolution. Am J Phys Anthropol, 140:751–758, 2009. © 2009 Wiley-Liss, Inc.